Page 34 - Medicinal Chemistry Self Assessment

Section 1 General Self Assessment

1.7

Drug Metabolism 1.7 Drug Metabolism

1.7
1. Heroin is a synthetic derivative of the naturally occurring opioid analgesic morphine. Given its illicit into
Drug Metabolism
morphine. Which phase I transformation is responsible for the conversion of heroin to morphine?
1. Heroin is a synthetic derivative of the naturally occurring opioid analgesic morphine. Given its illicit nature,

heroin is not subject to Food and Drug Administration (FDA) regulation; therefore, the actual composition

of a given heroin batch varies significantly. The three molecules drawn below represent the three major
1. Heroin is a synthetic derivative of the naturally occurring opioid analgesic morphine. Given its illicit into
components found within a batch of heroin. The users’ intense rush has been attributed to the conver-
morphine. Which phase I transformation is responsible for the conversion of heroin to morphine?
sion of heroin into morphine. Which phase I transformation is responsible for the conversion of heroin to
morphine?

Heroin Morphine

Heroin Morphine
2. Estradiol, the estrogen component of many oral contraceptives, undergoes a phase II conjugation

reabsorbed (at least in part). Consider the structure of estradiol drawn below and do the following:
2. Estradiol, the estrogen component of many oral contraceptives, undergoes a phase II conjugation reac-
tion to produce a metabolite that is eliminated via a fecal route (at least in part). The conjugated hormone
a. Modify the structure drawn below to show the product of a sulfate conjugation (phase II
2. Estradiol, the estrogen component of many oral contraceptives, undergoes a phase II conjugation
undergoes a process called enterohepatic recycling. In this process the sulfate conjugate is cleaved by gut
bacteria to regenerate the active drug, which is then reabsorbed (at least in part). Consider the structure of
transformation).
reabsorbed (at least in part). Consider the structure of estradiol drawn below and do the following:
estradiol drawn below and do the following:
b. Which enzyme is required to make this sulfate conjugate?
a. Modify the structure drawn below to show the product of a sulfate conjugation (phase II
a. Modify the structure drawn below to show the product of a sulfate conjugation (phase II
transformation).
c. Which deconjugating enzyme catalyzes removal of the sulfate group thus allowing for
transformation).
b. Which enzyme is required to make this sulfate conjugate?
enterohepatic recycling?
c. Which deconjugating enzyme catalyzes removal of the sulfate group thus allowing for
b. Which enzyme is required to make this sulfate conjugate?
enterohepatic recycling?

c. Which deconjugating enzyme catalyzes removal of the sulfate group thus allowing for
enterohepatic recycling?

Estradiol

Estradiol

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